ESD safety

[Doodski]

Has anyone tried to ESD protect a standard office chair? I have a Sidiz T50 in my study and I often get loud crackling through my iLoud monitors when I get up and then a shock from the next metal thing I touch - this has been enough to condition me to be wary of metal door handles regardless of my location.

I know that ESD office chairs are a thing. Has anyone tried to ESD proof a standard chair? I happy with my T50 in all other respects and loathed to replace it with something else without attempting to fix the ESD issue.

I was thinking of purchasing some 'Faraday' tape and attaching is to some strategic locations on the chair and then grounding it using an ESD wrist strap.

There are ESD safe floor coatings, fabric coatings, clothing coatings etc. All discharge the ES at a safe rate.

 

[DonH56]

Most major electronic suppliers have sections on ESD control (Allied, Arrow, Digikey, Mouser, etc.) as well as lab material supply houses (don't have a list of them in mind). What works for your chair depends somewhat in its construction. Our lab chairs had a short metal chain dangling down from the chair's central support shaft (metal) to connect to the treated lab floor; it also works if you have an ESD floor mat. The chair's cushions came in a couple of types: one was treated with a spray that you renewed once a year or so, and the others had conductive material woven into the chair's seat cloth. There were chains/wires/strips of metal tying seat, arms, and support shaft together to drain to that dangling grounding chain.

In the past, with a standard office chair, I had some success by using an ESD floor mat grounded to the wall outlet (via the usual 1 M resistor), and attaching a small (gauge) wire to the base of the chair to contact the floor, screwed to the chair's support shaft, and continuing up to the seat where I just glued a bare segment of wire to the cushion. I left a large loop to allow the chair to move up and down and turn, but of course every now and then one my my boys would grab and spin the chair so I'd have to replace the wire to the seat. The wire was one long piece since the chair had a plastic cover over the support shaft, making it harder to just tap it at the top and bottom.

 

[Speedskater]

So I went up in the attic and found two catalogs:

Techni-tool. They have a section on "Static Protection"

https://www.techni-tool.com/

Zack Electronics
There 1999 print catalog had 17 pages on Static Control and Clean Rooms. But I can't find that section on-line.

Zack Electronics - Audio, Video, Wire, Components, Cable, Connectors & Datacom Professionals

Zack Electronics is a leading West Coast distributor specializing in wire, cables, connectors, and installation solutions for audio, video, broadcast, and datacom professionals.

www.zackelectronics.com

 

[Berwhale]

Electrostatic charges come into existence when 2 non conductive materials are rubbed together of pulled apart.
That charge can't go anywhere when walking on carpets or something with isolation between feet and ground.
That charge can accumulate on the body (which is conductive).
Once you touch something that is grounded (other potential) the electrons will find a way though your body to the ground potential.
Spark flies and you can feel a jolt if enough electrons leave your body at once.

Your non ESD chair has isolating materials, isolating feet and and the floor, most likely, is also non conductive.
Riding/sliding on the floor = friction = charge building up. Getting on/off the chair or 'reseating' is friction = charge building up.
Touch something grounded and it flows away.

So... to get your chair to become ESD safe requires a slightly conductive (ESD) floor.
Wheels that are conductive (like car tires are)
Cloth on the chair that has wires in it or materials that conduct charges and do not create much when there is friction.

What you could do is wear an ESD wristband while on the chair that is tied (via a 1M resistor which usually is the wristband) which is connected to safety ground.
Once you got of the chair take it off or disconnect and you should have no charge to speak of.
Walk with friction on a carpet and its there again.

Thanks, yes I have a basic understanding of the principles. I have the chair (and myself) on a cotton rug which I have attached to earth via an ESD strap connected to a nearby central heating radiator (the copper piping of my radiator system being bonded to earth in several places). I've also made up an 'ESD solution' of water mixed with fabric conditioner and isopropyl alcohol. I have sprayed this on the rug and the chair. This does help, but it needs reapplying every few days and it's not an ideal solution (pun intended!)

 

[Berwhale]

There are ESD safe floor coatings, fabric coatings, clothing coatings etc. All discharge the ES at a safe rate.

Yes, I have researched this and attempted to replicate with my cheap ESD solution.

We also have the data centre floor coated with it at my work - it's not my cheap stuff though

 

[Berwhale]

In the past, with a standard office chair, I had some success by using an ESD floor mat grounded to the wall outlet (via the usual 1 M resistor), and attaching a small (gauge) wire to the base of the chair to contact the floor, screwed to the chair's support shaft, and continuing up to the seat where I just glued a bare segment of wire to the cushion. I left a large loop to allow the chair to move up and down and turn, but of course every now and then one my my boys would grab and spin the chair so I'd have to replace the wire to the seat. The wire was one long piece since the chair had a plastic cover over the support shaft, making it harder to just tap it at the top and bottom.

Thanks, this is exactly what I was thinking of. I have a grounded mains outlet about 2 feet from the stem of my office chair. I can buy a UK 1M grounding plug and wire the chair straight to it.

 

[Doodski]

Thanks, this is exactly what I was thinking of. I have a grounded mains outlet about 2 feet from the stem of my office chair. I can buy a UK 1M grounding plug and wire the chair straight to it.

After all this ESD safe stuff is in place remember to moisturize the arms and hands and wear a ESD approved lab coat and always strap in. ESD is insidious.